How to Improve Your Project Estimates

A recent question was asked on LinkedIn’s project management Q&A regarding estimates. The person was asking the community how effective their estimates tend to be. Since leaders are regularly asked to come up with estimates, I’ll share my response:

Thanks for serving up this question, Sam. It’s one nearly every project manager struggles with, regardless of what they say in their LinkedIn answers. šŸ˜‰

Whenever I hear someone say their estimates are always on track, I like to recall a quote from Ashleigh Brilliant: “To be sure of hitting the target, shoot first and, whatever you hit, call it the target.”

In my experience, the problem isn’t that we are bad at estimating–though we can get better. Rather, the problem is we don’t sufficiently understand the project. The more I can learn about a project, the better I can estimate its activities.

Of course that leads to a common and obvious problem: we’re asked to come up with estimates before we know enough to provide informed answers.

I have the true privilege of working with project managers and leaders from around the world, helping them deliver projects and lead teams. Here are some of the top lessons regarding project estimating that I use to coach project managers:

* You only know what you know. PMI’s concept of “rolling wave planning” means that we build a plan based on what we know and then progressively elaborate it as we learn more. That’s true with estimates as well. Never give a more granular estimate than you have information to support it. You can say, “We’ll deliver this project at 4:30pm on July 31” but I’m here to tell you that you won’t–or at least using the path that you thought. One of the best DBA’s I ever managed had this line: “The project schedule is the schedule of exactly how the project will not occur!” That’s not an excuse to avoid planning–it’s just a reminder that your plan (and thus estimates) will need to be modified. Don’t worry about getting your numbers perfect. Work on knowing your project better. Giving ranges or confidence factors early on–if you can get away with it–is a much better practice.

* Estimates are based on assumptions. If you think a project is going to take three times longer than your boss thinks, it’s likely that you’re talking about two different projects. Estimates are heavily based on assumptions–often unwritten or even realized. In debate training we’re taught to never attack another person’s position. Rather, attack their assumptions and inferences. Don’t get into an argument about why your estimate is good or bad. Rather, compare assumptions with the person who is trying to persuade you. If they can’t shoot down your assumptions, it is more difficult to shoot down your estimate.

* Learn new techniques. Many project managers haven’t been exposed to the three-point estimating technique (sometimes referred to as weighted average or PERT). Instead of coming up with one estimate, you come up with three: optimistic, pessimistic, and most likely. Then you apply the formula: Estimate = (Optimistic + ( 4 * Most Likely ) + Pessimistic) / 6. It’s not magic but it’s an example of an approach that tries to bring some structure to an inherently ambiguous situation. There are many other techniques beyond this. My point is there are some really smart people who have figured out some structured ways to come up with better estimates. It’s worth reading some good books or articles on the topic.

* No involvement, no commitment. Get people closest to the work involved with estimates. It’s been said “There’s an inverse relationship between your level in a company and your ability to see reality!” People who do the work can give you better numbers–plus they are more likely to accept them since they came up with them.

There’s so much more I’d love to share but space is limited. I cover these and related topics in my free video series at

Sam, I wish you much continued success with your projects!

Andy Kaufman, PMP
Host of The People and Projects Podcast

BTW, one reason I share this is to make sure you know about LinkedIn’s “Answers” module. It’s a great resource for those with questions to tap into insights from around the world. Beyond that, it’s another way to improve your online expertise. If you answer a question and it gets selected by the asker as the Best Answer, LinkedIn tracks it. Over time, it helps continue to position you as an expert in your field. I highly recommend you check it out!

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